There is a demo in Sphinx demos folder.
It shows that when a OTP is generated, a Sphinx event is fired so you get the OTP and set it to the user. I'm not sure if you checked the demo and if that's the question?
To be honest i've not run any demo ....
I need oly a code generation (not QR or similar), i'll send this code via sms and / or via email for signature purpose.
Thank you for the attention.
And there you have the project group with the demo files.
If you need to do any user verification "before" login, I recommend you just leverage this to your application. Let users register and/or login with Sphinx, but then only accept the user in your application after you do additional checks with it, if you need to.